COMPARATIVE STUDIES ON POLYPHENOLS PROFILE AND ANTIOXIDATIVE ACTIVITY OF SOME BERRY FRUITS

The fruits of raspberry, blackcurrant, gooseberry, redcurrant, and blueberry were evaluated for their content of total phenols (TP) and phenol fractions - nonflavonoid and flavonoid phenols (NFP, FP), total flavanols (F-3-ols), non-tannin and tannin phenols (NTanP, TanP), and total anthocyanins (AC). The antiradical (DPPH center dot) activity and ferric reducing antioxidant power (FRAP) of the ethanol fruit extracts were assayed as well. It has been found that the fruits studied are characterised by high content of phenol compounds and manifest pronounced antioxidant activity. The content of TP and phenol fractions varies depending on the fruit genotype and the antioxidant activity correlates with TP and phenol fractions. The highest values of TP content were obtained from blueberry fruits - 3500 mg/kg GAB, and the lowest 1350 mg/kg GAB - from the red currant. The antiradical activity of these fruits is 6.18 and 5.13 mM TEAC, and the ferric reducing antioxidant power - 4.80 and 2.11 mM AAE, respectively. FRAP value was highly correlated with anthocyanins content (r(2)= 0.9978), whereas TP content was relatively less correlated with DPPH center dot (r(2)= 0.5524).